1 /* 2 User DMA 3 4 Copyright (C) 2003-2004 Kevin Thayer <nufan_wfk at yahoo.com> 5 Copyright (C) 2004 Chris Kennedy <c@groovy.org> 6 Copyright (C) 2005-2007 Hans Verkuil <hverkuil@xs4all.nl> 7 8 This program is free software; you can redistribute it and/or modify 9 it under the terms of the GNU General Public License as published by 10 the Free Software Foundation; either version 2 of the License, or 11 (at your option) any later version. 12 13 This program is distributed in the hope that it will be useful, 14 but WITHOUT ANY WARRANTY; without even the implied warranty of 15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 16 GNU General Public License for more details. 17 18 You should have received a copy of the GNU General Public License 19 along with this program; if not, write to the Free Software 20 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 21 */ 22 23 #include "ivtv-driver.h" 24 #include "ivtv-udma.h" 25 26 void ivtv_udma_get_page_info(struct ivtv_dma_page_info *dma_page, unsigned long first, unsigned long size) 27 { 28 dma_page->uaddr = first & PAGE_MASK; 29 dma_page->offset = first & ~PAGE_MASK; 30 dma_page->tail = 1 + ((first+size-1) & ~PAGE_MASK); 31 dma_page->first = (first & PAGE_MASK) >> PAGE_SHIFT; 32 dma_page->last = ((first+size-1) & PAGE_MASK) >> PAGE_SHIFT; 33 dma_page->page_count = dma_page->last - dma_page->first + 1; 34 if (dma_page->page_count == 1) dma_page->tail -= dma_page->offset; 35 } 36 37 int ivtv_udma_fill_sg_list (struct ivtv_user_dma *dma, struct ivtv_dma_page_info *dma_page, int map_offset) 38 { 39 int i, offset; 40 unsigned long flags; 41 42 if (map_offset < 0) 43 return map_offset; 44 45 offset = dma_page->offset; 46 47 /* Fill SG Array with new values */ 48 for (i = 0; i < dma_page->page_count; i++) { 49 unsigned int len = (i == dma_page->page_count - 1) ? 50 dma_page->tail : PAGE_SIZE - offset; 51 52 if (PageHighMem(dma->map[map_offset])) { 53 void *src; 54 55 if (dma->bouncemap[map_offset] == NULL) 56 dma->bouncemap[map_offset] = alloc_page(GFP_KERNEL); 57 if (dma->bouncemap[map_offset] == NULL) 58 return -1; 59 local_irq_save(flags); 60 src = kmap_atomic(dma->map[map_offset]) + offset; 61 memcpy(page_address(dma->bouncemap[map_offset]) + offset, src, len); 62 kunmap_atomic(src); 63 local_irq_restore(flags); 64 sg_set_page(&dma->SGlist[map_offset], dma->bouncemap[map_offset], len, offset); 65 } 66 else { 67 sg_set_page(&dma->SGlist[map_offset], dma->map[map_offset], len, offset); 68 } 69 offset = 0; 70 map_offset++; 71 } 72 return map_offset; 73 } 74 75 void ivtv_udma_fill_sg_array (struct ivtv_user_dma *dma, u32 buffer_offset, u32 buffer_offset_2, u32 split) { 76 int i; 77 struct scatterlist *sg; 78 79 for (i = 0, sg = dma->SGlist; i < dma->SG_length; i++, sg = sg_next(sg)) { 80 dma->SGarray[i].size = cpu_to_le32(sg_dma_len(sg)); 81 dma->SGarray[i].src = cpu_to_le32(sg_dma_address(sg)); 82 dma->SGarray[i].dst = cpu_to_le32(buffer_offset); 83 buffer_offset += sg_dma_len(sg); 84 85 split -= sg_dma_len(sg); 86 if (split == 0) 87 buffer_offset = buffer_offset_2; 88 } 89 } 90 91 /* User DMA Buffers */ 92 void ivtv_udma_alloc(struct ivtv *itv) 93 { 94 if (itv->udma.SG_handle == 0) { 95 /* Map DMA Page Array Buffer */ 96 itv->udma.SG_handle = pci_map_single(itv->pdev, itv->udma.SGarray, 97 sizeof(itv->udma.SGarray), PCI_DMA_TODEVICE); 98 ivtv_udma_sync_for_cpu(itv); 99 } 100 } 101 102 int ivtv_udma_setup(struct ivtv *itv, unsigned long ivtv_dest_addr, 103 void __user *userbuf, int size_in_bytes) 104 { 105 struct ivtv_dma_page_info user_dma; 106 struct ivtv_user_dma *dma = &itv->udma; 107 int i, err; 108 109 IVTV_DEBUG_DMA("ivtv_udma_setup, dst: 0x%08x\n", (unsigned int)ivtv_dest_addr); 110 111 /* Still in USE */ 112 if (dma->SG_length || dma->page_count) { 113 IVTV_DEBUG_WARN("ivtv_udma_setup: SG_length %d page_count %d still full?\n", 114 dma->SG_length, dma->page_count); 115 return -EBUSY; 116 } 117 118 ivtv_udma_get_page_info(&user_dma, (unsigned long)userbuf, size_in_bytes); 119 120 if (user_dma.page_count <= 0) { 121 IVTV_DEBUG_WARN("ivtv_udma_setup: Error %d page_count from %d bytes %d offset\n", 122 user_dma.page_count, size_in_bytes, user_dma.offset); 123 return -EINVAL; 124 } 125 126 /* Get user pages for DMA Xfer */ 127 down_read(¤t->mm->mmap_sem); 128 err = get_user_pages(current, current->mm, 129 user_dma.uaddr, user_dma.page_count, 0, 1, dma->map, NULL); 130 up_read(¤t->mm->mmap_sem); 131 132 if (user_dma.page_count != err) { 133 IVTV_DEBUG_WARN("failed to map user pages, returned %d instead of %d\n", 134 err, user_dma.page_count); 135 if (err >= 0) { 136 for (i = 0; i < err; i++) 137 put_page(dma->map[i]); 138 return -EINVAL; 139 } 140 return err; 141 } 142 143 dma->page_count = user_dma.page_count; 144 145 /* Fill SG List with new values */ 146 if (ivtv_udma_fill_sg_list(dma, &user_dma, 0) < 0) { 147 for (i = 0; i < dma->page_count; i++) { 148 put_page(dma->map[i]); 149 } 150 dma->page_count = 0; 151 return -ENOMEM; 152 } 153 154 /* Map SG List */ 155 dma->SG_length = pci_map_sg(itv->pdev, dma->SGlist, dma->page_count, PCI_DMA_TODEVICE); 156 157 /* Fill SG Array with new values */ 158 ivtv_udma_fill_sg_array (dma, ivtv_dest_addr, 0, -1); 159 160 /* Tag SG Array with Interrupt Bit */ 161 dma->SGarray[dma->SG_length - 1].size |= cpu_to_le32(0x80000000); 162 163 ivtv_udma_sync_for_device(itv); 164 return dma->page_count; 165 } 166 167 void ivtv_udma_unmap(struct ivtv *itv) 168 { 169 struct ivtv_user_dma *dma = &itv->udma; 170 int i; 171 172 IVTV_DEBUG_INFO("ivtv_unmap_user_dma\n"); 173 174 /* Nothing to free */ 175 if (dma->page_count == 0) 176 return; 177 178 /* Unmap Scatterlist */ 179 if (dma->SG_length) { 180 pci_unmap_sg(itv->pdev, dma->SGlist, dma->page_count, PCI_DMA_TODEVICE); 181 dma->SG_length = 0; 182 } 183 /* sync DMA */ 184 ivtv_udma_sync_for_cpu(itv); 185 186 /* Release User Pages */ 187 for (i = 0; i < dma->page_count; i++) { 188 put_page(dma->map[i]); 189 } 190 dma->page_count = 0; 191 } 192 193 void ivtv_udma_free(struct ivtv *itv) 194 { 195 int i; 196 197 /* Unmap SG Array */ 198 if (itv->udma.SG_handle) { 199 pci_unmap_single(itv->pdev, itv->udma.SG_handle, 200 sizeof(itv->udma.SGarray), PCI_DMA_TODEVICE); 201 } 202 203 /* Unmap Scatterlist */ 204 if (itv->udma.SG_length) { 205 pci_unmap_sg(itv->pdev, itv->udma.SGlist, itv->udma.page_count, PCI_DMA_TODEVICE); 206 } 207 208 for (i = 0; i < IVTV_DMA_SG_OSD_ENT; i++) { 209 if (itv->udma.bouncemap[i]) 210 __free_page(itv->udma.bouncemap[i]); 211 } 212 } 213 214 void ivtv_udma_start(struct ivtv *itv) 215 { 216 IVTV_DEBUG_DMA("start UDMA\n"); 217 write_reg(itv->udma.SG_handle, IVTV_REG_DECDMAADDR); 218 write_reg_sync(read_reg(IVTV_REG_DMAXFER) | 0x01, IVTV_REG_DMAXFER); 219 set_bit(IVTV_F_I_DMA, &itv->i_flags); 220 set_bit(IVTV_F_I_UDMA, &itv->i_flags); 221 clear_bit(IVTV_F_I_UDMA_PENDING, &itv->i_flags); 222 } 223 224 void ivtv_udma_prepare(struct ivtv *itv) 225 { 226 unsigned long flags; 227 228 spin_lock_irqsave(&itv->dma_reg_lock, flags); 229 if (!test_bit(IVTV_F_I_DMA, &itv->i_flags)) 230 ivtv_udma_start(itv); 231 else 232 set_bit(IVTV_F_I_UDMA_PENDING, &itv->i_flags); 233 spin_unlock_irqrestore(&itv->dma_reg_lock, flags); 234 } 235